Poster Presentation Australian Society for Microbiology Annual Scientific Meeting 2024

Fifteen Years of External Quality Assessment in the Laboratory Detection and Diagnosis of Anthrax (#201)

Alexa Kaufer 1 , Katherine Lau 1 , Torsten Theis 1 , William Rawlinson 2
  1. RCPAQAP, St Leonards, NSW, Australia
  2. Serology and Virology Division (SAViD) SEALS Microbiology, NSW Health Pathology, SOMS, BABS, Women’s and Children’s, University of NSW, Randwick, NSW, Australia

Anthrax is a rare but serious infectious disease caused by the gram-positive bacilli known as Bacillus anthracis. Although anthrax is primarily a disease of domesticated and wild animals, humans can become infected if they come into contact with infected animals or contaminated animal products or if the organism is released intentionally or accidentally.

Since 2008, access and handling of Bacillus anthracis has been regulated under the Security Sensitive Biological Agents (SSBA) Regulatory Scheme. Funding was subsequently made available through the Australian Government Department of Health and Aged Care to establish the Biosecurity program at the Royal College of Pathologists of Australasia Quality Assurance Programs (RCPAQAP) to provide an External Quality Assessment (EQA) program for the detection of Bacillus anthracis. In 2013, this program was expanded to provide EQA programs for detecting Tier 1 and Tier 2 SSBA, other potential agents and communicable disease threats.

Since 2009, the RCPAQAP Biosecurity has offered EQA programs for the detection of Bacillus anthracis. Thirty-one programs have been offered in a variety of formats, including Specimen Modules, Biopreparedness Exercises, Whole-genome Sequencing (WGS) Modules, and Virtual Modules. To ensure participants were given every opportunity to improve the quality of their testing, laboratories were challenged with mixed samples, closely related organisms and samples with inhibitory substances or low bacterial count.

Laboratories have routinely reported several different microbiological, biochemical and molecular assays for the detection of Bacillus anthracis. The introduction of the BioFire Biothreat Panel in 2019 was a significant development and saw a shift from most laboratories using real-time PCR, to using the single-use, multiplex pouches. This also saw a shift in what some laboratories were classifying attenuated strains of B. anthracis, when the Biothreat panel identifies a strain lacking one of the virulence plasmids as Bacillus species.

Over the past fifteen years, survey results have shown that laboratories are proficient in ruling out or confirming the presence of anthrax. The introduction of new diagnostics such as the BioFire and WGS demonstrates the importance of continued participation in EQA, ensuring laboratories reliably use these methods to aid in diagnosing anthrax and correctly reporting and interpreting these results.